Features

For instruments: Thermo MAT262

"Plug-in" Compatible

High Sensitivity

Low Noise

High Gain

Long Life

Stable in air

ETP Active Film Multipliers™ are the latest development in electron multiplier technology. They incorporate a discrete dynode structure and are designed specifically for use where high sensitivity, low noise and longer operation life is demanded.

Description

For instruments: Thermo MAT262

Line-Of-Sight (LOS) particle entry for magnetic sector instruments and other charged and neutral particle detection. High current with chimney mounted to ion input aperture option. This increases the sustained output current limit for linear operation to 70 micro amps and decreases the internal resistance to 10% of the standard value. All units are bakeable to 350 °C.

Specs

Type

Light of Sight

Description

LOS input, pulse counting applications

Sensitive Area (mm)

7 x 12

Mechanical Envelope Dimensions

20 x 24 x 86

Maximum Dark Current (pA) / Counts (cts/min) at 2.5kV

1/3

Internal resistance (MΩ)

3.24

Number of Dynodes

22

Gain Curve (see chart)

A

Typical Gain at 2.0kV (when new)

4 x 1067

Technical

Care and Handling

ETP Electron Multipliers are incorporated as original equipment in all areas of mass spectrometry and surface science, as well as a diverse range of analytical and
general physics applications. They offer the performance required by modern
instrumentation and have a proven reputation for reliability and ruggedness.

The original packing supplied by ETP is suitable for long term storage. The
multiplier is enclosed in two sealed plastic bags. The outer bag contains a silica gel package to minimize adsorption of moisture, which could otherwise lead to
excessive outgassing upon installation.
Contained in its original packaging, the shelf-life of an ETP Electron Multiplier is guaranteed for up to two years from the date of shipment. If it is necessary to store the multiplier outside its original packaging, it should be kept in a clean, dust-free, low-humidity environment, such as a glass desiccator.

In order to minimize contamination, standard high-vacuum techniques are
recommended when handling ETP Electron Multipliers. Clean, powder-free nitrile or
latex gloves or finger cots should be worn to prevent the transfer of skin oils to
critical or mounting surfaces of the multiplier. All tools, mountings, and equipment
should be thoroughly cleaned (see instrument manual) prior to coming in contact
with the multiplier.

(WARNING) Care should be taken to minimize exposure of the multiplier to dust or
other airborne contamination. Dust particles within the detector may result in
increased background noise during operation.

(WARNING) Exposure of the multiplier to high humidity should be avoided in order
to minimize outgassing during initial operation. Excessive noise due to adsorbed
moisture may be rectified by leaving the multiplier under high vacuum for 24 hours

Active Film

ACTIVE FILM Multipliers™ are a new development in
multiplier technology that incorporate totally air-stable "ACTIVE
FILM" materials into a discrete-dynode multiplier design to produce an
exceptionally sensitive ion detector with long operating life and
excellent air stability. ACTIVE FILM Multipliers™ give a
combination of performance and durability unsurpassed by any other
type of electron multiplier detector.

ACTIVE FILM Multipliers™ are a new type of electron multiplier detector for mass spectrometry and represent the latest development in electron multiplier technology.

ACTIVE FILM Multipliers™ combine the wide dynamic range and longevity of discrete-dynode multipliers, with the compact size and air stability of continuous-dynode multipliers.

ACTIVE FILM Multipliers™ are completely air-stable while exhibiting extremely wide dynamic range, long operational life, and very high sensitivity.

Installation

Installing and Operating

ETP Electron Multipliers generally require no preconditioning if stored correctly.
The multiplier should be installed according to the instrument manufacturer’s
instructions. There should be no sharp objects in close proximity to the entrance
aperture as this could result in noise during operation.
Operating pressure should be as low as possible for best lifetime and minimum
noise. To avoid risk of damage due to discharge or arcing, the multiplier should not
be operated at a pressure in excess of 1 x 10-4 Torr.

(WARNING) Applying the maximum rated supply voltage to a new multiplier can
cause damage and permanent loss of gain.

(WARNING) Do not increase the applied voltage to a multiplier to overcome
background noise as this can cause permanent loss of gain.

Obtaining Optimum Lifetime from an
ETP Electron Multiplier

Operational life varies depending on application and can be affected by the
following factors:

Operating Environment: Lower operating pressure and lower partial
pressure of hydrocarbons in the vacuum chamber will result in increased
operational life, all other conditions remaining the same.

Operating Gain:
Operation should always be at the lowest applied voltage
consistent with good signal acquisition. In general, the lower the gain, the
longer the life of the multiplier. The gain of a electron multiplier will fall
gradually over time, requiring the applied voltage to be periodically
increased. This is a normal part of the multiplier aging process.

Output Current: Multiplier lifetime is inversely proportional to average
output current. Excessive input signals should be avoided, especially when
operating at high gain.

Rapid degradation of multiplier performance may result from failure of the vacuum
pumping system. This may cause severe contamination of the detector or damage
due to arcing caused by the sudden increase in chamber pressure. Degradation
caused by vacuum failure may be permanent and irreversible, especially if the
multiplier supply voltage was ON during the vacuum failure.

NOTE: Due to the wide variety of applications and environmental conditions within
instruments, there is no warranty on the operational lifetime of any electron
multiplier.